Case flap opener



June 16, 1959 B. J. NIQRELLI ETAL CASE FLAP OPENER Filed Oct. 22, 1957 QN QN @v A a mw n mw. v NNW NN W ...||a|| i I :l l ridire. ,MNNNNH H .wh -..H n,... a am H w 5.@ @u lll l?, N. WN .QQN m. N @NI Zw QQ wQH EN. ma( .w o adm l www. mm. Q5 mm. .www .N Q n June 16, 1959 5 Sheets-Sh-eet 2 Filed Oct.u 2 2, 1957 NWN n e a r rtw hxl Ina.

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CASE FLAP OPENER 5 Sheets-Sheet 3 Filed 0G17. 22. 1957 June 16, 1959 B. .L NIGRELLI. ETL 2,890,560,

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CASE FLAP OPENER 5 Sheets-Sheet -5 Filed Oct. 22. 1957 UnitedSttcs Patent Oce 2,890,560 Patented June v1b, 1959 CASE FLAP OPENER Biagio J. Nigrelli, Northbrook, Wendell E. Standley, Lake Forest, and Mariano V. Artiaga, lChicago, Ill., assignors to Ralph W. Johns, Biagio J. Nigrelli, and Robert R. Johns, |Chicago, Ill., a co-partnership doing business as Johns-Nigrelli-Johns Application 'October 22, 1957, Serial No. 691,647 14 Claims. (Cl. 53-382) The present invention relates to mechanism for opening the cover iiaps of shipping cases or containers and more particularly relates to mechanism for raisingand spreading outwardly the hinged flaps of paperboard shipping cases which have been previously emptied Aand the ilaps of which have been temporarily folded inward;

According to a commonly accepted present day practice empty cans and bottles, immediately after manufacture, are placed in corrugated paperboard or solid fibre shipping cases of the type having hinged closure flaps on side and end walls. The closure flaps are swung to closed position but not sealed and the illed cases of empty cans or bottles are shipped in this condition to the user, such as a manufacturer and packer of foods or beverages. When it is desired to fill the cans or bottles the flaps of the cases are raised either manually or mechanically, the contents removed and the empty cases are then either placed in temporary storage or placed on a conveyor for delivery to a part of the packing plant where filled cans or bottles are ready to be loaded into the empty cases. As soon as the cases have4 been emptied the cover flaps are usually folded back over the top of the case approximately to their closed position. This is usually done manually with the result that the cover aps when turned inward assume various angles. In elongated cases the short end flaps are usually folded in first and the tlonger side flaps are folded to overlie the end flaps. Sometimes the end flaps will assume a downwardly inclined position inside the case with the side aps lying flat, or in approximately iiat position, over the end aps. The positions of the flaps may depend upon several factors, such as, thestrengthand stiffness of the paperboard, how heavily the score lines have been impressed, and the length of time the ilaps have been held in closed position before the contents have been removed. if the flaps have little resistance to folding, the operator will sometimes fold the end iiaps well down into the cases and they may remain as folded. If the cases are made from rather stiif paperboard the end flaps when turned in may assume an upwardly inclined position and the side flaps consequently will not be `folded in to any great extent but may remain substantially vertical or may assume an upwardly and outwardly inclined position.

It is an important object of the invention to provide completely automatic mechanism for receiving empty cases of which some or all of the cover flaps have been folded inward and folding such ilaps upwardly to positions which will permit the cases to be efficiently loaded with filled cans or bottles, as desired. v

Another object of the invention is to provide case flap opening mechanism adapted Ito feed empty closed cases of the type above referred to in predetermined spacd relation to the ap opening or raising mechanism, and operating such mechanism in synchronism with the movement of the cases to lift and swing upwardly and outwardly each of the closure flaps carried by the side and end walls. I

j ceeds and will be set forth in Another object of the invention is to provide a feeding conveyor having release means timed with the ilap opening devices whereby cases will be delivered automatically at the desired point in the cycle of movement of the opening devices.

Another object is to provide improved means for causing preliminary upward swinging movement of the side wall flaps by flexing the side wallsinwardly.

Other and more specific objects and advantages of the invention will become apparent as the description prothe claims at the end of the specification.

In the drawings showing a preferred embodiment of the invention: I

l Fig. 1 is a fragmentary plan View illustrating the principal portion of the machine including means for'flexing the case side walls;

Fig. 1a is a fragmentary plan view of the receiving conveyor, including release means, showing an end portion of the principal conveyor and also showing the same case side wall flexing means as included in Fig. 1;

Fig. 2 is a side elevation of the mechanism shown in Fig. 1;

Fig. 2a is a side elevation of a portion of the mechanism shown in Fig. 2;

Fig. 3 is a fragmentary cross sectional view taken along line 3-3 of Fig. 1 look-ing in the direction of the arrows and showing two cases being carried in spaced relation past the flap opening devices;

Fig. 4 is a cross sectional View taken along line 4-4 of Fig. 3 looking in the ,direction of the arrows;

' Figs. 5 and 6 are perspective views of a conventional form of paperboard shipping case illustrating two possible arrangements of closure flaps, Fig. 5 showing the end closure flaps in a somewhat less common arrangement in which such aps bear against the ends of the side wall flaps, and Fig. 6 showing a more common arrangement in which the end flaps underlie the partly infolded side wall aps;

Fig. 7 is a fragmentary perspective View of the parts near the discharge end of the machine showing how all of the flaps are positively held in outwardly extended position as the case is conveyed;

Figs. 8 to 13, inclusive, are somewhat diagrammatic side elevational views, partly in section, showing the progression of the empty cases through the machine.

The mechanism of the present invention as herein disclosed comprises a feeding conveyor for holding two or more cases and a main conveyor for carrying the cases past the members which act upon the cover flaps. The feeding conveyor includes means to cause one case at a time to be fed to the main conveyor. The drive for the main conveyor and for the members acting upon the cover flaps is taken from a common drive means whereby the conveyor and ap opening mechanism operate in synchronism. The cases are rst conveyed through a station at which the side walls are flexed inward to insure partial upward swinging of the aps hinged on the tops of the side walls. Suitable mechanism next operates to swing downward the leading end wall iiap, causing this flap to pass horizontally beneath a stationary plow means which is adapted to engage the side wall flaps and swing such flaps upward and outward. Extended portions hold. the side wall flaps outwardly extended for the remainder of the distance of travel of the main conveyor.

With the side wall flaps held outwardly extended, a subsequent step is to swing upward the tiap on the trailing end of the case. A movable means is provided having a part which enters the case and travels in the same direction but slower than the case travels. This part engages below the flap on the trailing end wall if l'such flap is disposed in an inwardly and downwardly inclined position and swings it` up to approximately a vertical posttion. Substantially at the same time another movable means has a part which enters the case and engages the iiap carried by the leading end wall and swings the alp to an upwardly extended position. An additional movable means then engages the ap on the leading end wall and moves it forwardly and outwardly to a position enabling it to pass below a stationary hold-down means. Finally a movable means engages the upraised ap on the trailing end wall and swings it rearwardly of the case so that it will remain in rearward position when it passes beneath the hold-down means. The case thus reaches the end of the main conveyor with all aps outwardly extended and ready for delivery to a station, not herein shown, for loading the case.

Referring more particularly to the drawings, Figs. l and la taken together show the machine in plan except it is to be noted that a portion of the mechanism is illustrated in both views. The cases, indicated as a whole at 1, 1, are conveyed along two aligned conveyor sections, each indicated as a whole at 2 and 3. Conveyor 2 may be referred to conveniently as the feeding conveyor and conveyor 3 as the main conveyor. In the broad aspects of the invention the two conveyors constitute a unitary conveying means.

The cases may be of conventional form as regularly utilized in the shipment of canned or bottled goods, and are herein represented as the ordinary tubular form of container made of corrugated or solid fibre paperboard, frequently referred to as regular slotted containers. This form of container has vsets of upper and lower closure flaps. For simplicity only the upper aps are herein shown. The cases may be of various dimensions but for purposes, of illustration they are shown somewhat elongated, comprising side walls 4, 4 and end walls 5 and 6. The side walls carry at their upper edges hinged aps 7, 7 which are designed to meet centrally of the top. The end walls carry flaps 8 and 9, herein shown to be the same dimension normal to the upper wall edges as the side wall aps.

Conveyor 3 is suitably supported within a main frame composed of vertical frame members 10, 10, longitudinal members 11, 11, and transverse members 12, 12.

The cases are supported on guides 13 and 14 carried respectively on angle iron frame members 15 and 15a on the vertical webs of which are welded clips 16, 16 which include an interiorly threaded portion to receive threaded shafts 17, 17 having their ends journalled in fixed blocks 18, 18 and 19, 19 secured to the vertical frame members 10. The frame members 15 and 15a may be raised or lowered to adapt the machine for cases of varying heights by sprockets 20 secured to the vertical shafts 17, the sprockets being rotated in unison by means of a suitably driven sprocket chain 21, all in a manner which is well known.

The frame for conveyor 2 comprises longitudinally extending web members 24, 24 joined by transverse members 25, 25. Shafts 26 and 27 are journalled in brackets 28, 28 and 29, 29 depending from the longitudinal frame members 24, 24. These shafts carry pairs of belt pulleys 30, 30 and 31, 31 over which travel belts 32 and 33. Pulleys 31, 31 are keyed or otherwise secured to the shaft 27.

The outer end of the frame of conveyor 2 is preferably supported on downwardly depending leg members one of which is shown at 37 having a laterally projecting flange portion 38 into which an adjusting screw 39 is threaded whereby, upon rotation of the adjusting screw, the frame or conveyor 2 may be raised or lowered. The inner end of the frame of conveyor 2 is preferably joined pivotally to an extended frame portion 42 having journals 43 through which passes shaft 27 on the conveyor 2. Guide members 46 and 47 are preferably provided to keep the cases centered on the conveyor belts 32 and 33. These members are suitably secured on the frame members 24,

24 and extend forwardly to positions near the ends of the guide members 13 and 14 on the conveyor 3.

The cases are preferably conveyed along the guide members of conveyor 3 by a sprocket chain 50 having a plurality of equi-spaced iiight or pusher elements 51, 51 thereon, having a spacing which is preferably substantially greater than the lengths of the cases to be handled. The belts 32 and 33 could be independently driven if desired, but it is preferred to drive the belts directly from the chain 50. For this purpose the chain 50 is arranged to travel over a sprocket 52 keyed to shaft 27.

While conveyor 2 has been indicated in the drawings to be of limited length it should be understood that it may be considerably longer. As an alternative, conveyor 2 may have aligned therewith a suitable auxiliary conveyor, such as a vgravity type roller conveyor or a chute, which will constantly deliver additional cases to the feeding conveyor as soon as cases have left it and have been delivered to conveyor 3. Cases may also be delivered regularly by hand to conveyor 2 to replace cases transferred to conveyor 3.

Means are provided for holding the cases on conveyor 2 and releasing one case at a time for delivery to conveyor 3. For this purpose an intermittently operable stop mechanism is employed which will release one case to permit the moving belts to deliver it onto the guide members 13, 14 in proper timed relation with the movement of one of the iiight elements 51 on the chain S0. The flight element will move around sprocket 52 and up between the belts 32 and 33 to contact the trailing end wall of the case and propel it past the flap opening members. As shown in Figs. la and 2a, a stop 56, carrying rollers 57 at its upper end, is secured on the end of a bar S8 pivoted on a fpin 59 secured transversely of the conveyor frame. A spring 60, having one end secured to the frame and the other end secured to the end of bar 58 beyond the pivot pin 59, urges the stop 56 upward toward its case-holding position.

In order to cause the stop to be removed from its holding position in timed relation with the movement of the flights 51, a rotating cam element 63 is provided bearing upwardly against a roller carried by the bar 58. The cam is secured on a shaft 64, journalled in suitable depending brackets on the frame members 24, 24. This shaft carries a sprocket 66 driven through chain 67, passing over a sprocket 68 of a suitable size on the end of shaft 27. See Fig. la. The sizes of sprockets 66 and 68 are so selected that, for the passage of each ight around sprocket 52, the stop 56 will move through one cycle. Thus, just prior to the movement of a iiight 51 into upright position in its passage around sprocket 52, the cam 63 will have moved so that its high side causes lifting of the rear end of bar 58 to withdraw the stop 56, allowing the cases on conveyor 2, which are abutted end to end, to move forward. The leading case will move onto the guides 13 and 14 with its trailing end approximately above the shaft 27 in position to be engaged by a ight 51.

Just before the next advancing case, indicated at C1 in Fig. 2a, reaches stop 56 the timing is such that the stop will rise up against the bottom near the trailing end of the released case. This does not stop the case in its movement for the reason that it will be propelled forward by the oncoming cases even though its front portion may be lifted momentarily out of contact with the belts 32 and 33. The released case will be moved forward and its rear end will slip oif the top of the stop 56. This movement is facilitated by the rollers 57 at the upper end of the stop. The belts 32 and 33 have a suitable friction surface so that the belts may move beneath the cases while the cases are held stationary but the cases will be caused to move promptly once the forward case is-released. After the released case slips off the stop and drops back onto the belts such case will be caused to continue to move onto the guides 13 and 14 to a point where its rear end will be only lightly engaged by the moving belts. In general practice the move; ment of the cases is rapid and the cases are not subjected to any substantial amount of abrasion by the belts.

The guides 13 and 14 are so related and constructed that cases may move relatively freely into position at the receiving end of conveyor 3. Thereafter, during their forward movement, the cases will be somewhat restrained by a degree of pressure applied against the side walls, so that they will be at all times firmly contacted by one of the conveyor ights and will not be advanced out of contact with such iiights by action of the flap treating elements. The guide member 14 may be in the form of a relatively light angle iron secured to the horizontal web of the angle iron frame member 15a. The guide member 13 is in two separate parts and comprises a vertical portion 13a and a horizontal portion 13b. This latter portion is secured to the underlying horizontal web of angle iron frame member 15. The vertically disposed portion 13a is spring tensioned and adjustable laterally toward and from the opposite guide member 14. For this purpose brackets 13C, 13e are secured on the frame members 15. These brackets each have an upright prtion apertured to receive a threaded stud 13d secured yto the rear face of the element 13a. A coil spring 13C surrounds the stud and bears at one end against the bracket and at the other end against a nut on the stud. A nut on the end of the stud bearing against the outside of the bracket limits the inward movement of the stud. By proper adjustment of the nuts on stud 13d the vertical guide portion 13a may be positioned to exert the desired amount of frictional resistance against the case side wall.

In order to admit the case freely to a position between the guides, the vertical part 13a has an outwardly oiset section 13f, preferably of a length somewhat in excess of the longest case the machine is designed to handle. Additionally, the horizontal part 13b and the horizontal web of the angle iron guide 14 may be curved downward at their ends, as indicated at 48 and 48a; and the vertical part 13f and the vertical web of the guide 14 may be ared outward, as indicated at 49 and 49a.

After each case is engaged and moved forward along the guides 13 and 14 by a ight 51 it is desirable to make certain that the side wall aps are in at least a slightly raised position to permit the flaps to be engaged by iiap raising means, herein shown as rearwardly diverging plow bars 71, 71, having their ends disposed centrally of the conveyor and spaced slightly above the upper edges of the end walls of the case. While various means may be employed for this preliminary raising of the side wall iaps it is preferred to apply inward flexing pressure on the side walls which will tend to flex or distort the hinge lines between the side walls and their attached flaps and by so doing cause the aps to swing upward. To obtain this result cylinders 72, 72 are positioned one on each side of the path of travel of the cases. Within each cylinder is a piston connected with a piston rod 73 bearing a head 74 having a roller 75 at its end. A supply of air under pressure is fed to each cylinder through a conduit 76, a valve 77 and a conduit 78. The valve 77 is a usual form of three-way valve. In one position air under pressure is directed through the valve behind the pistons to cause the rollers 75to be thrust forward to engage the side walls of a case. In a second position the port admitting air under pressure is closed, the conduit 78 is opened to the atmosphere and air under pressure is admitted to the opposite side of the piston, causing retraction of the roller 75 from the case side wall. The operating stem 79 of the valve 75 is actuated in time with the conveyor 3. For this purpose a cam 80 is secured on shaft 64 and, `as shaft 64 rotates, produces periodic Imovement ofthe valve stem to the left as viewed in Fig. 2a. TheV valve stem is spring loaded to urge it to the right so that the roller 81 0n the .valve stem will at all times bear upon thesurface of the cam. The timing is such that, as the mid-portion of each case passes the deliecting mechanism, the pistons will be extended into contact with the case side Walls and held briefly in such contact until the side wall flaps leading edges have time to reach the rotary element next to be described.

Means are provided for swinging the leading end wall aps either forwardly beneath the plows 71, 71, or rearwardly to substantially the plane of the top edges lof the case walls so that the leading flap will not interfere with the action of the plows in swinging the side wall flaps upward and outward. This means in the present instance comprises a rotary element 83 having two symmetrical curved surfaces 84a, 84b each terminating in a finger portion, indicated at a and 85b respectively. The element 83 is fixed on a shaft S6 which is driven in time with the movement of flights 51 so that the linger portions 85a and 85b will move with the case. That is, the element 83 will rotate counterclockwise as viewed in the drawings, and finger element 85a will pass clear of the upper edge of the leading end wall of the case. If the flap on the leading wall is extending upward and outward, as shown in Fig. 8, the finger will engage the flap and move it downward, preferably somewhat past its horizontal position. Thus, as the leading edge of the ap advances to a point even with the ends of the plows 71, the flap will be depressed sufiiciently to pass beneath the plow ends. As the plow ends are somewhat spaced apart, the fingers 85a and 85b may readily pass between the plow ends.

In the event the flap on the leading end wall is folded inward and upward, the finger 85a of course, will not engage the flap, and the ap will be moved down and will be positively held down momentarily by the curved surface portion 84a until the case has advanced to a position where the plows are in effective contact with the side wall flaps. In the event that the flap 8 on the leading end wall is one that is disposed in a downward and inward inclined position, due to the lack of resistance of the hinge, or for other reasons, the element 83 will merely pass through -this part of its cycle without influencing the ap.

The flap contacting and moving elements are illustrated in Figs. 8 to 13, inclusive, as they appear in passing through a complete cycle. Beginning in Fig. 8, a case designated A is shown on the left and traveling toward the right. This case has had its side walls deflected inward to cause the side wall flaps 7, 7 to swing partially upward. Fig. 11, 12 and 13 are taken at a location somewhat farther advanced along the machine, so case A is shown in Fig. ll also at the extreme left and advancing toward the center of the view in Figs. 12 and 13. The cases to the right of case A, designated as A2, indicate a preceding case which has `advanced through all of the positions indicated by case A. The case A2 in Fig. 8 may be considered as a continuation of the representation of case A in Fig. 13.

As case A advances from the position shown in Fig. 9 to that shown in Fig. l0, the advancing end wall flap passes out from under the ends of the plows and is permitted to swing up if the hinge connection would naturally cause this movement. It is not necessary that this leading flap be held down during its movement in this area of the operation.

The element 83 is driven to make one complete rotation while the conveyor moves the length of the space between two adjacent liights. In the latter half of its cycle of rotation the finger 85b and curved surface 84h are moving downward and forward, see Figs. l1 to 13, so that if the ap on the trailing wall is projecting inward of the case and inclined upward the nger 85b will depress it to cause it to pass beneath the ends of the plows. If the trailing ap is in a rearward inclined position the curved surface 8411 will swing it down to a'sub-` stantially horizontal plane and it will be so maintained as it passes beneath the ends of the yplows. In the event that the flap 9 on the trailing wall is one that maintains a downward and inward inclined position, due to the lack of resistance of the hinge, or for other reasons, the element 83 will merely pass through this part of its cycle without inuencing the ap.

At the position of the 'case A as shown in Fig. 12 rotary member 83 has completed its functions on case A and the plows have swung the side wall fiaps outward. Rods 88, 88, which are preferably formed as extended portions of the plows 71, serve to retain the side wall flaps in an outward extended position as the case continues in its travel along the conveyor 3.

In the event the ap 9 on the trailing end wall is directed inward, it is necessary to swing this flap ont of the case to an upright position. For this purpose a constantly rotatable, approximately S-shaped, element 89 is employed fixed on a stub shaft 90. The end portions 91a and 91b are bent at substantially a right angle to the central part of the element 89 and the length of the central portion is sut`n`cient to bring the ends 91a and 91b down into the case, as it travels, to a position somewhat below the lower free edge of the downward and inward inclined ap. See particularly Figs. 3 and 9. In the present instance the element 89 is rotated at one-half the speed of element 83, Iand each end portion 91a and 91b individually operates on successive cases. Reference rst to Figs. 1l, 12 and 13 and next to Figs. 8, 9 and 10 makes clear how element 89 operates. As the case advances, one end of element 89, herein shown as 91a, beings to swing down in a counterclockwise movement to enter the top of case A. As shown in Fig. 13 the end portion 91a is just beginning to enter the case. The next view of this sequence is shown at the right in Fig. 8 in which the case, now designated A2, is approximately centrally positioned beneath the shaft 90 0n which element 89 is secured. The end portion 91a may still dip lower into the case as shown in the next view, Fig. 9. At this location the end of the flap begins to catch up with the portion 91a and begins to slide therealong with the result that the ap begins to swing upward. This action continues as the portion 91a begins to leave the top of the case. This may be seen by comparing Figs. 10 and 11.

When the flap 9 nally passes from contact with the end portion 91a, occurring shortly after the position is reached that is shown in Fig. 11, it is desirable to hold this ap at least momentarily from swinging back down toward a horizontal position. For this purpose pegs 94, 94 are employed (see particularly Figs. 1 and 3) which extend inward suiciently to be contacted by the lateral edges of the flap. The pegs are adjustably attached to the side frames 11 by means of a base part 95 to which the peg is permanently secured. This base has a threaded opening to receive screws 96 which extend through a slot 97 in the frame. By loosening the screws 96 the base may be moved a small distance forward or rearward and, by retightening the screws, the peg may be secured in the desired position.

The principal function of the pegs 94 is to hold the flap 9 from swinging forward for enough time to permit the end of a rotary element 100 to come into position whereby one of its ends can bear against the upwardly presented surface of the flap. See Fig. l2. Element 100 is secured on shaft 101 driven to rotate counterclockwise at the same speed as element 89 and the end of the element 100 will follow along with ap 9 as the case advances until the flap enters beneath the curved end portion 102 of hold-down rail 103, adjustable longitudinally by the slot and bolt connection indicated at 104.

At approximately the same time as the flap 9 is being lifted by the element 89, other means become operative to lift and swing upward and outward the ap 8 on the leading end wall of the case in the event that this ap has remained in an inward and downward inclined position from the time it was placed on conveyor 2 and has therefore not been inuenced by rotary element 83. This means as herein disclosed comprises a rotaable element 105 having a curved, hook-like portion 106 terminating in a bent end 108 extending approximately in a direction tangential to the arc described by such end. The element 105 is secured on a stub shaft 107 rotatable counterclockwise 'at the same speed as element 83.

The movement of element 105 is so timed with the conveyor that its end 108 will reach a maximum distance into the case when the case approaches a central position beneath the shaft 107. The curved end portion 106 is preferably of a length to extend a substantial distance into the case, so that the bent end portion 108 will engage beneath the leading end wall flap 8. In Fig. 8 the curved portion 106 is to be seen moving down toward the top of the case. In Fig. 9 the end 108 of portion 106 is approaching the edge of the ap and in Fig. 10 the end 108 has contacted the flap and has raised it. This completes the function of the curved end 106 and the flap is now in a position to be acted upon by other means presently to be described.

In the event the ap 8 on the leading end wall has been swung forward by element 83 and has remained in such position, as shown in Figs. 8, 9 and 10, the curved end 106 will not intiuence the ap and therefore other means are provided to insure that the advancing edge of the ap will pass below the pegs 94, 94. This means comprises an arm 109 extending from rotatable element 105 in a direction approximately at a right angle to the part from which the curved portion 106 extends. As shown in Fig. 13, the arm 109 engages the ap 8 and moves it somewhat forward and downward as shown at the right of Fig. 8, wherein the alternate position of ap 8 is shown in broken lines. The arm 109 stays in contact with the ap until its end has been brought beneath the pegs 94, 94. It is thus apparent that the ap 8, whether folded within the case or swung forwardly, will be brought to upright position by the rotary element 105, either by the curved end portion 106 or by the arm 109. Thus, by the time the forward end wall passes the pegs 94, the ap 8 will be approximately upright and beyond the pegs.

When the flap 8 has thus been brought to raised position the next step is to move it to an approximately horizontal, outwardly extended position. For this purpose an arm 112, having a transversely extending stud portion 111, carrying a disc 113 near its outer end, is rotatable in a -counterclockwise direction about shaft 101 and independently driven. The speed at which arm 112 is driven is preferably such that it will rotate twice during the passage of each ight 51 and by so doing, will contact the forward flap 8 of each passing case. As shown in Fig. 10 the disc 113 carried -by arm 112 is almost in position to Contact the flap 8. In Fig. 1l the ap 8 is shown lin full line position as having been contacted by the disc 113 and directed forwardly so that the free edge of the ap slides under the curved end 102 of the hold-down rail 103. Two intermediate positions of the case are indicated by showing in bre-ken lines only the leading wall 6 and the ap 8.

After the leading wall flap 8 has been swung down and slid below the hold-down rail 103, the case continues to move forward and the element will contact the trailing wall flap 9, as previously explained, and this ap will be swung rearward prior to its passage below the rail 103.

Near the discharge end of conveyor 3 an outer pair of hold-down rails 114, 114 may be employed which are in effect continuations of the rods 88.

The driving means for the various flap contacting elements will now be described. A motor 117 is connected through a gear box 118 to rotate a main drive shaft 1-19 journalled in suitable bearings on the machine frame. Keyed to the shaft is a sprocket 120 around which passes the conveyor chain 50 of conveyor 3. At the other end of conveyor 3 the chain passes around sprocket 52 on shaft 27, as p-reviously explained. A shaft 121 is journalled near the lower ends of the upright frame members 10, 10, and is driven by a sprocket 122 thereon through a chain 123 passing over a sprocket 124 on the shaft 119. At the other end of shaft 121 is secured a sprocket 126 which drives a stub shaft 127 through a chain 128 passing around sprocket 129 secured to the end of the stub shaft. The stub shaft 127 is journalled in the side frame 11 and in a supplemental bracket 130 secured at the upper part of the machine. See Figs. 1 and 2.

The shaft 101 to which rotary element 100 is secured extends across the machine and has its ends journalled in the side frame members 11, 11. This shaft 100 carries a spur gear 132 which is keyed thereon and which meshes with a gear 133 keyed on stub shaft 127. The gear ratio is such that shaft 101 will be caused to make one-half a revolution while the conveyor chain travels a distance equal to the spacing between flights.

In order to rotate the arm 112, bearing the disc 113, the arm is secured to a pinion 136 which is mounted on shaft 101 to rotate freely and is held in place by collars 137, 137 fixed on the shaft 101. The pinion 136 meshes with a gear 138 keyed on stub shaft 127. As shown in Fig. l, the disc 113 as previously described is carried on the stud portion 111 extending at a right angle to the main part of the arm, and the arm is suiciently long whereby the stud and disc 113 may pass around the gear 138 on the end of stub shaft 127 without interference. The gear sizes 4are selected so that the arm 112 will make two revolutions during the time the conveyor chain moves one ilight spacing.

For the purpose of driving the hook-like element 105 secured to shaft 107, the shaft has a sprocket 141 thereon which is driven b-y a chain 142 passing around sprocket 143 secured on shaft 101. See Fig. l. The sizes of the sprockets are selected so that element 105 will make one revolution while the conveyor chain moves one flight spacing. The stub shaft 107 is journalled at one end in frame 11 and intermediate its ends in a supplemental bracket 140 carried on the frame 11.

For the purpose of driving the S-shaped element 89 on the stub shaft 90 a sprocket 144 is secured on this shaft. This sprocket is driven by a chain 145 which passes around a sprocket 146 fixed on shaft 101. The sizes of the sprockets are selected so that element 89 will make one-half a revolution while the conveyor chain moves one llight spacing. The stub shaft 90 is journalled in frame member 11 and in a bracket 147 carried thereon. In order to drive the rotary element 83 fixed on shaft 86 this'shaft has a sprocket 149 keyed thereon, driven by a chain 150 passing around a sprocket 151 on shaft 90. The sizes of the sprockets are selected so that the rotary element 83 will make one revolution while the conveyor chain moves one ilight spacing.

Means are provided for adjusting the p-lows 71 and hold-down rails 88. For this purpose threaded adjusting rods 154 are secured at their lower ends to short, bent bar sections 155 secured to the rear sides of the plows 71 by welding. The vertical threaded end of each screw is held in the horizontal web of a suitable angle bracket 156 by means of nuts which can be tightened against the horizontal web of the bracket. A somewhat similar arrangement is used for the holddown rails S8. This comprises a threaded stud or rod 157 welded at its lower end to each rail 88 and having its other end adjustably secured in a bracket 158. In practice the plows 71 and hold-down rails 88 may be formed of metal rods which have a degree of llexibility so that if desired each plow may be formed integral with its companion hold-down rail.

The piston-cylinder means for flexing the case side walls may be adjusted, both vertically and in and out transversely to the travel of the cases. For this adjustment each cylinder may be secured on a plate 161 slidable in and out on the horizontal portion of an angle iron bracket 162 provided with a pair of bolts 163 arranged to extend through a slot 164 in the plate. The bracket 162 has a vertical portion 165 including a web contacting flat against the frame member 11. This vertical portion is slotted at 166 so that it may be held in various vertically adjusted positions by bolts held in the frame member 11 and extending through the slots.

To summarize the `operation of the mechanism-the motor is started to operate the conveyors and ilap treating devices. Empty paperboard cases, having their flaps either fully or partially folded over, as typified in Figs. 5 and 6, are then delivered to conveyor 2, either manually or by a suitable conveyor. The empty cases are propelled in endwise abutted relation along conveyor 2 on the constantly moving belts 32 and 33 until the leading case reaches stop 56. As soon as one of the flights 51 on the chain 50 of conveyor 3 approaches the sprocket 52 the stop will be withdrawn by the action of the continually rotating cam 63 and the belts Will propel the leading case onto the guides 15 ready to be propelled forward along the guides by such ight 51.

When the case propelled by flight 51 travels a short distance along the guides the side walls are deflected inward by the action of the rollers 75, on the pistons 73, 73, controlled by the cam actuated valve 77. This dellection of the side walls causes inward bending of the ilap hinge lines with the result that the ilaps, if folded over the top of the case, will be caused to swing upward. Pressure is maintained on the side walls through only a brief period but sulllciently long so that the forward corner portions of the flaps will be brought into positions where they can engage the element 83. Thus, if there should be a tendency for the ilaps to reassume a at position over the case, they will be held up by their engagement against the rotary element.

The rotary element 83 rotates once in a counterclockwise direction, as Viewed in the drawings, while the conveyor chain moves the distance of one flight spacing. By so doing, both the leading and trailing end wall ilaps may be influenced by one of the two fingers a or 85b, which serve to fold the llap toward a horizontal plane if the flap is directed forward and will cause it to slide beneath the ends of plows 71, 71. If either end llap is directed rearward and not engaged by a finger as it moves past the end of the case one of the curved surfaces 84a or 84b will fold the flap further rearward to approximately a horizontal position.

The side wall flaps in passing the plows 71 are caused to assume an outward extended position and will be so held by the rails 88 during further travel of the case along conveyor 3.

The case next passes beneath the S-shaped element 89 rotating counterclockwise one revolution while the conveyor chain travels the distance of two ilight spacings so that the opposite ends will enter successive cases. If the trailing end wall flap is directed inward and downward the end of element 89 will be engaged by the edge of the flap and the flap will be swung to an upright position as shown in Figs. 9, 10 and l1.

At approximately the same time the S-shaped element acts upon the trailing wall llap, the hook shaped element will act upon the leading wall ilap, assuming such flap is directed inward. This element turns counterclockwise one revolution while the conveyor chain travels the distance of one ilight spacing. The action of element 105 is best indicated in Figs. 8, 9 and l0.

In the event the ilap on the leading wall is directed forwardly and outwardly, as shown in the alternate broken line position in Fig. 8, the linger 109 on element of the pegs 94, 94 as viewed in Fig. 8.

When the ap on the trailing wall has been released by the S-shaped member S9 it will pass beneath the pegs 94, 94 and, prior to passing from contact with the pegs,

it will. be engaged by one end of element 100. This element like element S9 makes a full revolution while the conveyor chain moves the distance of two Hight spacings.

After the hook shaped portion 106 of element 105 passes out of contact with the leading wall flap leaving the ap projecting upward, it is almost immediately engaged by the disc 113 on arm 112 and swung forward and downward so that the outer free end of the flap will pass beneath the curved end of holddown rail 103. See Figs. 10 and ll. The arm 112 rotates twice during the time the conveyor chain travels one liight spacing.

The flap on the trailing wall, having been brought to upright position, will be swung down to horizontal position by contact with element 100. Then, after it passes beyond the inuence of element 100, it will move in beneath the end 102 of hold-down rail 103. At the end of conveyor 3 all of the aps of the case have been brought to an outward extended position and are so held by the side and central hold-down rails, as indicated in Fig. 7. At this point the case is ready to be delivered to additional mechanism designed to load the case with its contents.

From the foregoing it is apparent that there has been provided a combination of operating devices adapted to receive and convey empty cases which have had their aps temporarily turned inward. The conveyor for retention of a supply of empty cases is designed to feed one case at a time in coordination with the conveyor designed to carry the cases past ap treating devices which operate in such a manner and such sequence as to lift up and swing outward all four hinged closure flaps of a paperboard case of the type known as regular slotted containers, within wide limits of flap positioning. By first applying inward pressure to the case side walls the side wall aps are caused to swing up and immediately thereafter the leading end wall ap is either swung forward, if it happens to be outside the side aps, as shown in Fig. 5; or swung rearward and downward if this flap is inside the side aps, as shown in Fig. 6. By clearing the area at the upper end of the leading end wall the plows for the side wall flaps can perform their functions without interference which might otherwise cause the case to be torn and rendered useless.

Due to the employment of stub shafts for the elements 89 and 105, and by mounting the element 112 for movement independently about the shaft 101 on which element 100 is fixed to rotate with the shaft 101 there is obtained a very important degree of compactness of the mechanism which minimizes the length of the machine.

By the provision of means for vertically adjusting the guides 15, of conveyor 3 and the adjusting means for the piston-cylinder mechanism for side wall deection the mechanism is well adapted to handle cases of varying heights. By the provision of the adjustable connection indicated at 104 the curved end 102 may be moved forward or rearward to accommodate end wall flaps of varying lengths and assure that the edges of the flaps will be brought under the curved end 102 at the proper time in the movement of the case.

While the present description sets forth a preferred embodiment of the invention, numerous changes may be made in the construction without departing from the spirit of the invention, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

What is claimed is:

-1. Flap opening mechanism for elongated, rectangular cases of the type having side and end walls with closure aps hinged to the top edge of each wall, said mechanism comprising a conveyor for advancing the cases in upright position and in a direction aligned with their longitudinal axes, means for exing the case side walls inward to cause the side wall aps of each case to swing upward from flat position over the case to an upward and inward inclined position, stationary plow means disposed centrally over the conveyor at a height closely spaced above the upper edges of the case walls and adapted to engage the inner advancing edges of each of the upward and inward inclined side wall aps and swing them outward as the case is advanced, movable means located over the conveyor adapted to engage and swing outward and downward the end wall ap on the advancing end of the case to cause it to pass beneath the plow means, retaining members extending beyond the plow means, located above the conveyor and laterally of the side walls of the case to retain the side wall flaps in outwardly extended position as the case is advanced, said retaining members being separated laterally a suflicient distance to permit the leading end wall ap to swing upwardly after the ap has advanced beyond the plow means, movable means adapted to enter the open case and to engage the end ap on the trailing edge of the case and swing such ap upward in the event such end ap is folded inwardly, such means completing its function when such flap has been swung approximately to fully raised position, stationary holddown means for the leading and trailing end wall aps, movable means for engaging and swinging the leading end wall ap forward and downward below such holddown means, and additional movable means for engaging and swinging the trailing end wall flap rearward prior to its contact with the hold-down means.

2. Flap opening mechanism for rectangular cases made of foldable material, such as paperboard, and of the type provided with closure ilaps hinged to the top edges of each wall, said mechanism comprising a conveyor for advancing the cases with their closure aps folded inward in at least partial overlapping relation, plow means located in spaced relation to the conveyor in position to engage and swing outward the closure aps on the case walls extending parallel with the conveyor travel when such aps are in a partially raised position, means ahead of the plow means for causing the last mentioned flaps to be partially raised, and means movable in the same direction as the conveyor for swinging the flap on the leading case wall to substantially the plane of the top edges of the walls to cause it to pass clear of the plow means, whereby the plow means can act upon the two side closure flaps without interference with the leading wall closure flap.

3. Flap opening mechanism for four-wall, rectangular cases made of foldable material, such as paperboard, and of the type provided with closure flaps hinged to the top edges of each wall, said mechanism comprising a conveyor for advancing the cases in an upright position with their closure aps folded inward in at least partial overlapping relation, plow means located over the conveyor in position to engage the side closure aps on the case walls extending parallel with the conveyor travel when such aps are in a partially raised position, means ahead of the plow means for causing the last mentioned aps to be partially raised, and means movable in the same direction as the conveyor for swinging to horizontal position the flap on the leading case wall to cause it to pass beneath the plow means, whereby the plow means can act upon the two side closure aps without interference with the leading wall closure flap, said last mentioned means including surface portions for contacting and retaining the side closure flaps in their partially raised position until the case advances sufficiently for the plow means to engage beneath the advancing edge of said flaps.

4. Flap opening mechanism for four-wall, rectangular cases made of foldable material, such as paperboard, 4and 13 of the type provided with closure aps hinged to the top edges of each wall, said mechanism comprising a conveyor for advancing a case in upright position with the closure flap on the leading wall extending upward and with the llaps on the side walls inclined upward and inward, plow means disposed centrally over the conveyor with the front end of the plow means located in a position closely spaced above the top edges of the case walls, and means in advance of the plow means and operable in timed relation to the conveyor for contacting the iiap on the leading wall at a predetermined location on the conveyor and for moving such flap downward to a position at least no higher than the top edge of the leading wall, whereby such ap will pass below the front end of the plow means, said plow means having outward diverging portions extending to lines laterally outside the vertical planes of the side walls, whereby, when the case is advanced the plow means will engage beneath the edges of the side wall flaps and swing them upward and outward of the case.

5. In flap opening mechanism for empty, four-wall, rectangular cases made of foldable material, such as paperboard, and of the type provided with closure aps hingedfto the upper edges of each of the walls, said mechanism comprising in combination, a conveyor for ladvancing the cases with their closure flaps folded inward in at least partial overlapping relation, means for driving the conveyor, means operative during travel of the cases on the conveyor for raising and swinging outward the flaps on the case walls that are hinged in alignment with the travel of the cases, a rotatable arm mounted on pivot means spaced from the tops of cases carried by the conveyor and rotatable in the direction of travel of the conveyor, said arm having an angularly disposed end portion projecting in a direction rearwardly of the travel of the conveyor and adapted to enter a substantial distance into the top portion of the case, means for rotating the arm in time with the conveyor to cause the extremity of the arm and the rearwardly projecting portion to enter a case, whereby the rearwardly projecting portion can receive contact by the free edge portion of a downwardly inclined flap on the trailing case wall and cause lifting of the ilap as the case advances.

6. In ap raising mechanism for empty, four-wall, rectangular cases, such as paperboard, and of the type provided with closure flaps on at least two opposed walls, said mechanism comprising in combination a conveyor for advancing a case with the closure flaps carried on the leading and trailing walls and the flap on the trailing wall being folded inward of the case at a downward inclination, means for driving the conveyor, a rotatable arm mounted on pivot means spaced from the tops of cases carried by the conveyor and rotatable in the direction of travel of the conveyor, said arm having an angularly disposed end portion projecting in a direction rearwardly of the conveyor travel and adapted to enter a substantial distance within the case, means for rotating the arm in time with the conveyor to cause the extremity of the arm and the rearwardly projecting portion to enter a case, whereby the rearwardly projecting portion can receive contact of the free edge portion of a downwardly inclined flap on the trailing wall of a case and cause lifting of the ap as the case advances.

7. In ilap raising mechanism for empty, four-wall, rectangular cases made of foldable material, such as paperboard, and of the type provided with closure flaps on at least two opposed walls, said mechanism comprising in combination, a conveyor for advancing a case with the closure flaps carried on the leading and trailing walls and the flap on the leading wall being folded inward of the case at a downward inclination, means for driving the conveyor, a rotatable arm having a hook-shaped outer end portion mounted on pivot means spaced from the open tops of cases carried by the conveyor and rotatable in the direction of travel of the conveyor, the hook porr4 tion on the arm projecting forwardly of the conveyor travel and adapted to enter a substantial distance within the case, means for rotating the arm inl time With the conveyor to cause the extremity of the arm and its forwardly projecting hook portion to enter a case during its .forward movement and contact beneath the lower free edge of an inwardly and downwardly inclined flap on the .leading wall of a case and cause lifting of the flap as the case advances.

8. In flap raising mechanism for empty, four-wall, rectangular cases of the type provided with closure flaps hingedly carried on at least two opposed walls, said mechanism comprising in combination a conveyor for advancing a case with its closure flaps on the leading and trailing walls inclined downward inside the case, means for driving the conveyor, a pair of rotary arms mounted on parallel axes extending laterally of the conveyor and spaced from the tops of the cases carriedthereby, each rotary arm having a part extending longitudinally of the conveyor, in opposite directions and adapted to enter a substantial distance inside a case on the conveyor, and means for rotating said arms in time with the conveyor travel, the extending parts on said arms being adapted respectively to engage the aps on the leading and trailing walls of a case during rotation of the arms while the case is advancing on the conveyor and swing said flaps to upwardly inclined positions.

9. Flap raising mechanism for four-wall, rectangular cases made of foldable material, such as paperboard, and of the type provided with closure aps hinged to the top edges of at least two opposite walls, a continuously operable feeding conveyor for advancing a case in upright position with the walls that carry the flaps extending in alignment with the container travel, avmovable stop associated with the conveyor, a main conveyor for receiving cases from the feeding conveyor, said main conveyor having spaced flight elements adapted to engage and propel cases received from the feeding conveyor, means timed with the travel of the main conveyor for releasing the stop and causing delivery of a case to the main conveyor and for subsequently causing the stop to move to case-holding position to stop the next advancing case, and means located Ibeyond said stop and timed with the main conveyor for causing initial swinging of the side wall tllaps to inclined position over the case.

l0. Flap raising mechanism for four-wall, rectangular cases made of foldable material, such as paperboard, and of the type provided with closure aps hinged to the top edges of at least two opposite walls, a continuously operable feeding conveyor for advancing a case in upright position with the walls that carry the ilaps extending in alignment with the container travel, a movable stop associated with the conveyor, a main conveyor for receiving cases from the feeding conveyor, said main conveyor having spaced ight elements adapted to engage and propel cases received from the feeding conveyor, means timed with the travel of the main conveyor for releasing the stop and causing delivery of a case to the main conveyor and for subsequently causing the stop to move to caseholding position to stop the next advancing case, means located beyond said stop and timed with the main conveyor for causing initial upward swinging of the side wall ilaps to inclined position over the case, and common control means for said last mentioned means and the stop actuating means.

11. Flap raising mechanism for four-wall, rectangular cases made of folda'ble material, such as paperboard, and of the type provided with closure llaps hinged to the top edges of its walls, a main conveyor for conveying a case in upright position, equi-spaced ilights on the conveyor, each adapted to propel a case, means for driving the conveyor, llap raising means associated with the conveyor, means for operating the ap raising means in time with the flight movement, and a feeding conveyor driven from 'to the passage of the trailing end portion of the 15 the main conveyor and operable to deliver a case to the main conveyor in advance of each llight.

12. Flap raising mechanism for four-wall, rectangular cases made of foldable paperboard, and of the type provided with closure flaps hinged to the top edges of its walls, a main conveyor disposed horizontally for carrying a case in upright position, equi-spaced flights on the conveyor each adapted to propel a case, means for continuously driving the conveyor, means operable in time with such conveyor for swinging upward at least certain aps from inward extended positions over the case, a feeding conveyor aligned with the main conveyor, means for continuously driving the feeding conveyor, a movable stop near the discharge end of the feeding conveyor, and means timed with the travel of the main conveyor for moving the stop periodically from operative to inoperative position to release a case for delivery to the main conveyor in position to be engaged Vby a flight thereon.

13. A conveyor combination comprising a main conveyor adapted to carry rectangular cases in upright position, said conveyor including guides for the cases and a. conveyor chain having spaced tlights for propelling cases along the guides, a feeding conveyor having guides aligned with the main conveyor guides and having a belt for propelling cases along the guides in abutted relation, a movable stop for the feeding conveyor, means for continuously driving the main conveyor and the feeding conveyor, and means timed with the travel of the ights on the main conveyor for moving the stop to inoperative position to deliver one case tothe main conveyor guides prior to the movement of a flight into position to propel the case on the main conveyor, said stop moving means causing the return of the stop to operative position prior released case past the stop, whereby the stopis in positionto halt the next advancing case.

vdisposed main conveyor adapted to carry cases in 4conveyor chain rotatable on a 'conveyor including guides aligned with the main conveyor axis, spaced flights on v ing 16 Y 14. A conveyor combination comprising a horizontally upright position, said main conveyor including laterally spaced guides for the cases and an endless conveyor chain arranged to travel between the guides, a sprocket forV the horizontal axis, a feeding guides and a pair of spaced endless belts on which cases may be propelled in abutted relation toward the main conveyor, said spaced belts being arranged between the guides of the feeding conveyor and passing individually over spaced pulleys rotatable on a common horizontal the main conveyor chain adapted to engage against the trailing wall of a case to propel it, said flights being suiciently narrow to travel up between the belts for a distance ahead of the discharge ends of the belts, means for continuously driving the main conveyor and the feeding conveyor, a movable stop associated with the feeding conveyor, means timed with the travel of the flights on the main conveyor for moving the stop to inoperative position to deliver one case to the main conveyor guides prior to the movement of a flight into position to propel the case along the main conveyor, said stop movmeans causing the return of the stop to operative position prior to the passage of the trailing end portion of the released case past the stop, whereby the stop momentarily displaces the case at its trailing end and moves into position to halt the next advancing case.

References Cited in the le of this patent UNlTED STATES PATENTS Wahl et al. Dec. 9, 1952 2,656,060 Fischer et al. Oct. 20, 1953 2,684,799 Holstein July 27, 1954 2,685,975 Bruce Aug. 10, 1954 

